Devon Energy Tower, Office skyscraper in Downtown Houston, United States.

Two Allen Center, also called Devon Energy Tower, is a 36-floor, 521 ft (159 m) office skyscraper in downtown Houston completed in 1978 and designed by Lloyd Jones Brewer & Associates. It has travertine flooring and an Energy Star label, is owned by Brookfield Properties, and hosts the law firm Chamberlain Hrdlicka on floors 13 and 14.

Two Allen Center was completed in 1978, designed by Lloyd Jones Brewer & Associates, with all 36 floors given to offices. In 1989 it was known as the Citicorp Building and Exxon had office space there. Devon Energy kept its Houston office in the tower until announcing its closure in October 2012, affecting 500 jobs.

The tower's name comes from Devon Energy, which kept its Houston office here until announcing its closure in October 2012, a move affecting 500 jobs. Earlier the building was called the Citicorp Building, and in 1989 Exxon had office space in it. Today the Houston law firm Chamberlain Hrdlicka occupies the 13th and 14th floors.

Two Allen Center stands at 1200 Smith Street in downtown Houston, a short walk from the Allen Center complex and the downtown tunnels. It is a working office tower: the lobby and upper floors are for tenants and their visitors, so sightseeing inside is not possible. The building is Energy Star labelled.

The tower's name changed with its main tenant: it was the Citicorp Building in 1989, when Exxon had offices there, and later carried the Devon Energy name after that firm occupied space. Devon announced in October 2012 that it was closing its Houston office in the building, affecting 500 jobs.